58 



BULLETIN 983, U. S. DEPARTMENT OF AGRICULTURE. 



Practically all the commercially available coniferous woods of this 

 country are of equal value for alcohol production, and, as the waste 

 from them constitutes the greater portion of the mill waste of the 

 country, the results obtained from the experiments with them are 

 naturally the most interesting. Cypress and the cedars were not 

 tried; and the writer has no data to present regarding them except 

 commercial results obtained from cypress in mixture with longleaf 

 pine. As the exact composition of the mixture is not known, no 

 positive data can be offered; it may, however, be said that cypress 

 seems to give yields only from 60 to 75 per cent as good as pine. 



The different results obtained in cooks Nos. 50, 83, and 72 on 

 western larch are due to differences in material as well as in treatment. 

 The differences will be considered in greater detail later. Cook No. 

 50 was made on material from the butt log, which is usually left in the 

 woods, and with 1.8 per cent acid at 7.5 atmospheres for 10 minutes. 

 Cooks Nos. 72 and 83 were made with 2.5 per cent of acid, the first for 

 20 minutes and the second for 40 minutes. Unfortunately, all three 

 cooks were not made on material from . the same sample, although 

 cooks Nos. 72 and 83 were on the same sample and indicate a tendency 

 toward an increase of fermentable sugars with an increase in the 

 time of cooking. This tendency is probably due to pentose decompo- 

 sition, as it was with spruce. The high figure for total sugars is due 

 to the production of galactose, which is not fermentable under ordi- 

 nary conditions, and the figures for fermentable sugars are therefore 

 correspondingly lower than they are in the other coniferous woods. 



BROAD-LEAVED WOODS. 



The broad-leaved woods neither give the yields obtained from the 

 coniferous woods, nor do they exhibit the uniformity of yield shown 

 by the coniferous species. The yields of total sugars are sometimes 

 nearly as great as those obtained from the coniferous species; but, 

 as the following table shows, the portion of the total sugars ferment- 

 able is very much less than that from the coniferous species : 







Total re- 



Per cent of total 

 reducing sugars. 



Alcohol yields. 





















ducing 











Gallons 



Cook 

 No. 



Species of wood. 



sugars, 

 per cent 

 of origi- 

 nal dry 



wood. 







Per cent 



Gallons 



of 190- 

 proof per 







Fermen- 



Vnfer- 



of origi- 



of abso- 



drv ton 







table. 



mentable. 



nal drv 



lute per 



allowing 











wood. 



dry tons. 



5 percent 

















distilla- 

















tion loss. 



62 



Birch 



20.53 



46.29 



53.71 



4.288 



12.97 



12.95 



73 



Hard maple 



18.93 



34.04 



65.96 



3.029 



9.16 



9.14 





Silver maple 



20.74 



47.22 



52.78 



4.661 



14.10 



14.07 



76 



Beech 



21.24 



22.22 



77.78 



1.995 



6.03 



6.02 



77 





17.30 

 18.38 

 18. 30 

 16.60 



50.48 

 30.40 

 38.86 

 26.79 



49.52 

 69.59 

 61.14 

 73.21 



4.102 

 2.675 

 3.205 

 1.382 



12.40 



12. 38 



78 





8. 09 8. 07 



79 





9.69 

 5.99 



9.67 



80 



Slippery elm 



5.98 



81 



Red piim ....... 



20.42 

 18.19 



38.81 

 32.86 



61.19 

 67.14 



3.658 

 2.392 



11.06 

 7.23 



11.03 



82 





7.21 









